Radial flow elastic fluid turbine



0d. 2v2, 1940. R. o. J. MLLE-R RADIAL FLOW ELASTIG FLUID TURBINE Filed Aug. 1, 1938 Patented oct. 22, 1940 Application August 1, 1938,v Serial N o. 222,469

In Sweden August` 19, 19,37' a.

i 3 Claims.

invention relates to double rotation turbines for elastic fluid, hereinafterfor the sake of simplicity-referred to as steam, of the radial flow type in which there are two or more axially spaced group'sof concentric bladings `which are passed inf series bythe steam so that the group offblladings-tobe first passed bythe steam and the groupto be last passed-*by the steam are actuated at opposite ends of' the'turbine; I-Ii-therto, it was common practice to-admitysteam to the'said rstmentioned group of'bladings, that is, the high pressure system of the turbine, from-a steam chest located at the same end' ofY thel turbine wher'efthe said group of bladings was situated. This method of supplying the driving iiuid may easily be found,l as there is only need of those channelslin thev turbine disc which are ordinarily providedgv in connection with double rotation turbines in order' to effect a communication between the steam chest andthe innermost portion of `the-said group of bladings, that is, thev high pressure system. c In certainv turbine types, however, such as,'for instance, condensing turbines, the kgroup of bladings situated' at the end of the series, that is, the low pressure system, is of a i comparatively-large diameterand is, therefore' considerably heavier than the other group of bladings'foreachfofv the other groups of bladings. The distance between the centers of gravity of the two rotary turbine halves and the centers of the respective bearings will be quite different due to the unsymmetrical position of the heavier low pressure system. As a result, the deflections of the shaft endswill be unequal and the turbine halves will obtain different critical numbers ofrevolutions.

The object of this invention is to provide a turbine of the type above set forth, hereinafter referred to as a multiple disc turbine, in which the low pressure system is situated substantially in the middle of the turbine and in which the centers of gravity f the two oppositely rotating turbine halves are situated at about equal distances from their respective bearing centers.

The invention is characterized, chiefly, by the fact that the steam chest of the multiple disc turbine is situated on the side of the turbine, where the low pressure system is situated, a connection for passing steam from this steam chest to the high pressure system situated on the other side of the turbine being provided by passages formed in the rotary turbine half next t0 the steam chest.

By moving in this way the steam chest from the (Cl. 253-165 )l system will be displaced towards the said rstf mentionedsde., As a result, the lowpressure system will obtain a more central position with relation to the turbine bearingsV and the turbine casing. This will afford several advantages, such -as substantially equal distances between the centers of gravity of thetwo oppositely rotating. turbine halves and the respective-bearing centers, nearly equal deiiections4 ofthe shaft ends,y and *much thel same critical numberl of revolutions` forl both turbine halves. Furthermore, the steam d-ischarged fromthe low. pressure systemwill flow out into. the central portion ofthe surrounding turbine casingywherebyy ample space will be availabley for the laterally expanding flow of steam as compared with the space available for said; steam inc-the Vhitherto known multiple disc turbines. in which the low pressure system is-situated on one side. of the. turbine casing.

Y As a rule, the steam chest is concentrically surrounded by one or more additional steam chambers for supplying overload steam. With the steam chambers arranged in conformity with the present invention, a higher overloading capacity may-be: obtained due to the fact that fresh steam may be -supplied directly to the low pressure system.. Previous1-y, this wasfpossibleonly by providing steam chests on both sides of the turbine. This, too, means a considerable advantage of the present invention.

The above described construction effects a good balancing of the turbine in axial direction due to the fact that the labyrinth packing on the low pressure side is in communication with the steam chest for the fresh steam and is thus fed with steam of high pressure. With the steam chest situated on the high pressure side, the

balancing steam has to be admitted to the labyrinth packing on the low pressure side through pipe lines extending from the steam chest. The invention renders this arrangement unnecessary and makes the construction more simple.

In the drawing, rone embodiment of a turbine constructed according to this invention is illustrated in a diagrammatic manner. The drawing shows an axial section of the upper portion of the turbine.

With reference to the drawing, the turbine is provided with three axially spaced groups of concentric bladings which are passed by the steam in succession. The numerals I and 2 indicate the ends of the two shafts otherwise not illustrated. 'Ihe shaft end I carries two turbine discs 3 and` 4. The shaft end 2 carries likewise two turbine discs 5 and 6, the latter of which being so constructed as to secure the disc 5 to the shaft end. The three groups of bladings are numbered 1, 8 and 9, respectively. High pressure steam is supplied through the pipe line I9 to a steam chest I0 situated on the same turbine side as the low pressure system 9, axially outside the same. The steam chest I is surrounded by an overload or bleeding chamber II which, though this is not shown in the drawing, is connected to the steam chest Il] or, by means of pipes likewise not shown, to some consumption 4apparatus for bleeding steam. Between the steam chambers and the turbine disc 5 is inserted a labyrinth packing I2. On the opposite side of the turbine there is a similar labyrinth packing I3. Surrounding the journals I and 2 are shaft packings Irl and i5, respectively. s

The group of concentric bladings 'I represents the high pressure system of the'turbine to be supplied with fresh steam. As above described,

` the steam chest IU, if arranged in the hitherto 'usual manner, would have been situated to the right ofthe labyrinth packing I3 vand in such case the fresh steam would have entered the group of bladings 'l through holes formed in the turbine disc 3. According to this invention, on the contrary, the steam chest IIIV is positioned on the side of the turbine, remote from the high pressure system l. In this case the fresh steam is admitted to the high pressure system] through passages I8 formed in the disc 5 and in disc 6 or its journal-like portion. The steam'thus admitted to the system l, then passes through the intermediate system 8 and, nally, through the low pressure system 9 to be then passed to a condenser, not shown.

A passage I6 extends through the turbine disc 3 and one disc of the labyrinth packing I3 to allow steam to flow from the space between the groups of bladings 1 and 8 to the inner periphery of the labyrinth packing I3 for balancing purposes. ie outer steam chamber Il communicates through passages I1 with the inner periphery of the low pressure system 9. If desired, steam may be discharged from the Space between the groups of bladings 8 and .9 through said passages I'I.

What I claim is:

1. A radial now elastic iiuid turbine comprising, in combination, a plurality of axially spaced groups of concentric bladings including a high pressure rotary system and a low pressure rotary system at axially opposite ends of said groups, said low pressure system being of a greater radial length than said high pressure system, a fluid chest situated axially outside said low pressure system on the side thereof remote from the high pressure system, and a conduit'between said fluid chest and the inlet end of said high pressure system.

2. A radial iiow elastic uid turbine comprising, in combination, two axially spaced shaft ends adapted to rotate in opposite directions, turbine discs and associated blades carried by said shaft ends forming a plurality of axially spaced groups of concentric bladings including a high pressure rotary system, a low pressure system and an intermediate system, said low pressure system being a-t one end of said group of systems and being of a greater radial length than either of the other systems, a fluid chamber surrounding the shaft end axially outside said low pressure system on the side lthereof remote from the other systems, a conduit extending between said fluid chamber and the inner end of the said high pressure system, another fluid chamber surrounding said rstmentioned fluid chamber, and a conduit between said other uid chamber and the inner end of said low pressure system.

3. A radial ow elastic fluid turbine comprising, in combination, two axially spaced shaft ends adapted to rotate in opposite directions, turbine discs and blades thereon carried by said shaft ends forming a plurality of axially spaced, radially extending uid passages connected alternately at their outer and inner ends, so as to be in series arrangement with relation to the flow of the fluid, the last passage of said series being of a greater radial length than the other passages, a iiuid chest situated axially outside said longer passage by the side thereof remote from the other passages, and a conduit leading directly from said y uid chest to the inlet end of the first ud passage of the series.

RAGNAR OLOV JACOB MILEIR.. 

